1. Field of the Invention
The invention relates to a dummy bar for a continuous casting installation for casting a metal strand and having a dummy bar head, a transition piece, and a link chain, wherein the transition piece is arranged between the dummy bar head and the link chain, wherein the transition piece and/or the link chain are formed of a plurality of links connected with each other in an articulated manner, and wherein the links are pivotable relative to each other about a transverse axis extending perpendicular to a longitudinal axis of the dummy bar. The invention further relates to a method of continuous casting a metal strand with which such a dummy bar is used.
2. Description of the Prior Art
A dummy bar of the type described above is used for starting a continuous casting process in a continuous casting installation. The mold of the continuous casting installation is closed at its outlet with the dummy bar head in order to be able to introduce melt into the mold in a first complete process; the dummy bar head prevents an immediate exit of the melt from the mold. After a first solidification, the formed strand is withdrawn from the mold, together with the dummy bar, and is transported over the strand guide of the continuous casting installation and a horizontal roller table. Subsequently, the dummy bar is again transported to the mold to be available for the next starting process. At so-called “top feeding,” the dummy bar is displaced in a loop through the continuous casting installation, i.e., behind a horizontal roller table, it is displaced upwardly to a level of the casting platform and is pulled onto a dummy bar rack and is transported again in direction of the mold.
Dummy bars of the above-described type are disclosed, e.g., in DE 2 103 417 A1, in EP 0 043 365 B1, in U.S. Pat. No. 4,632,175, and in DE 10 2006 023 503 B3.
Because the dummy bar head, as a rule, has a greater thickness than the following link chain, when the dummy bar rests flatly, e.g., on the dummy bar rack, from time to time, increased stresses are generated in the articulated joints; the link-shaped dummy bar buckles up. Therefore, the links or the articulated joints are subjected to an increased load which causes wear, in particular, when the dummy bar head together with the transition links lies on the dummy bar rack. This is particularly the case when at a relative pivotal movement, the articulated joints do not allow any evasion of the colliding chain links. In the stand-by and exchange position, the handling of the dummy bar is problematic, in particular when sections of the dummy bar need be replaced.
To this end, it is mostly necessary to lift the dummy bar with a crane in order to reduce the stresses in the articulated joints.